1. Field of the Invention
The invention generally relates to a display, and more particularly, to a driving circuit of a display.
2. Description of Related Art
FIG. 1 is a diagram of a conventional driving circuit for a display. Referring to FIG. 1, a driving circuit 100 includes a latch unit 105, a low-voltage buffer 110, a level shifter 120 and a buffer 130. The level shifter 120 converts an input voltage VIN into an output voltage VOUT with a larger voltage fluctuation.
When the voltage level of the input voltage VIN is changed, the level shifter 120 and the buffer 130 would simultaneously transit the levels thereof (a transition from a high-level to a low-level or from a low-level to a high-level). While the level shifter 120 is transiting, the level shifter 120 and the buffer 130 may conduct a large current due to a tri-state that the level shifter 120 and the buffer 130 are in, which would establish a larger voltage drop across a parasitic resistor of a ground terminal. Since the current path in a chip contains a parasitic resistance, the large current of the level shifter 120 and the buffer 130 conduct would pull up the voltage level of the ground terminal. At this time, if the level shifter 120 has a poor transition capability, a transition may fail in response to the voltage drop at the ground terminal.
A circuit, for example, a driving circuit of a liquid crystal display (LCD) is usually composed of multiple level shifters and multiple buffers, which conduct a larger current during the transiting thereof to increase the voltage drop of the ground terminal. Thus, the level shifters are more likely affected thereby and fail to transit.